Lindane vaporizer



April 21, 1959 L. E. KOPECKY 2,882,640

LINDANE VAPORIZER Filed Nov. 16, 1956 INVENTOR.

LOU/O Z. [OPEC/f) BY United States Patent LINDANE VAPORIZER Louis E.Kopecky, Hollister, Mo. Application November 16, 1956, Serial No.622,628

Claims. (Cl. 43-129) This invention relates to Vaporizers andparticularly to vaporizers which are used to vaporize an insecticidesuch as lindane for killing insects and disinfecting large areas such aswarehouses.

An eifective insecticide for killing insects and disinfecting largeareas is lindane, the gamma isomer of benzene hexachloride orl,2,3,4,5,6-hexachlorocyclohexane. When vaporized, this insecticide isodorless and invisible. The devices which are presently used forvaporizing such insecticides comprises a holder consisting of a cupwhich includes a fiat electrically heated plate on which the insecticideis placed. When electric current is supplied to the plate, the normallydry solid insecticide is liquified and evaporated. Such devices serve tovaporize some of the lindane but have certain disadvantages. Forexample, excessive heating of lindane results in the formation ofharmful oxides, wasteful oxidation of a portion of the lindane and areversion to some extent to the parent compound benzene hexachloride.

It is an object of this invention to provide a vaporizer which willefficiently vaporize lindane without formation of a liquid.

It is a further object of this invention to provide such a vaporizerwhich will vaporize lindane with a relatively small amount of heat.

It is a further object of this invention to provide such a vaporizerwhich will efliciently distribute the lindane vapors into theatmosphere.

In the drawings:

Fig. 1 is a plan view of the vaporizer.

Fig. 2 is a sectional view taken along the line 2-2 in Fig. 1.

As shown in the drawings, the vaporizer comprises a body of ceramic orplastic material which includes a hollow open-ended cup 11 provided withan integral hollow holder or bracket 12 extending from one side thereofand provided with means designated 13 for mounting the vaporizer on awall with the open end of cup 11 extending upwardly. Cup 11 is formedwith openings 14 at the base thereof which permit the ingress of air, aspresently described. The inside surface of cup 11 tapers upwardly andoutwardly. The body may also be made of pressed sheet metal or highheat-resistant plastics.

A ceramic or plastic tube 15 is provided within cup 11 and is supportedtherein by a peripheral flange 16 on the upper end thereof which engagesthe upper end of cup 11. Tube 15 is generally cylindrical and the innersurfaces 17 thereof taper or diverge upwardly. A resistance coil 18 iswound around the entire length of tube 15. Ends 19, 20 of the coilextend through hollow holder 12 and thereafter through an opening 21 inholder 12 to the exterior of the vaporizer. An electric plug 22 isattached to the end of the wires 19, 20 so that the plug may beconnected to an electric outlet in order to energize resistance coil 18.

A holder 23 for the chemical lindane is positioned within tube 15.Holder 23 is made of wire mesh defining a basket which is, as shown inFig. 1, generally triangular 2,882,640 Patented Apr. 21, 1959 in crosssection and comprises sides 24 and a bottom 25 with the upper end of theholder 23 being open. The lower end of tube 15 is provided with anopening 26. As shown in Fig. 2, the cross sectional area of holder 23 issuch, relative to the internal area of the lower end of tube 15, thatthe holder 23 is frictionally retained within tube 15. Holder 23 ispreferably made of brass, which does not stimulate oxidation of lindanein the presence of heat. Fibre glass mesh or other synthetic materialsmay be used if they are stable when exposed to heat and do not reactchemically with lindane.

In use, the vaporizer is mounted on a wall or other member in the areawhich is to be disinfected with tube 15 in generally vertical position.The insecticide in the form of crystals of lindane is poured into holder23 and plug 22 is inserted in an electric outlet causing resistance coil18 to be energized. The coil 18 applies heat uniformly to the materialin the holder 23. The lindane crystals in holder 23 are thereuponvaporized by sublimation, rise because of their inherent heat and passinto the atmosphere providing a mixture with air which is deadly toinsects. The upward movement of the lindane vapors and the air enteringthrough openings 14 in the base of cup 11 result in the formation ofconvection currents which move upwardly through openings 14 and opening26 in tube 15 through the lindane in holder 23 and out the upper end oftube 15 causing further sublimation of the lindane. The cup 11 serves toretain suflicient heat around tube 15 and holder 23 and also assists incontrolling the convection currents.

By this arrangement, there is a complete utilization of the lindanewithout causing any portion thereof to be liquified. In addition, noportion of the lindane is excessively heated and, as a result, theformation of harmful oxides is eliminated and there is no wastefuloxidation. In addition, the lindane does not revert to the parentcompound benzene hexachloride.

I claim:

1. In a vaporizer for lindane, the combination comprising a generallycup-shaped body having an open end, said body being adapted to bemounted in vertical position with the open end thereof extendingupwardly, said body having air intake openings adjacent the lower endthereof, a tube mounted within said body and extending generallyvertically, electrical heating means adapted to heat the lindanecomprising a resistance coil wound around said tube, and a perforatedholder for lindane mounted within said tube, said perforated holderbeing generally noncircular in cross section, the internal surface ofsaid tube tapering upwardly and the internal diameter of the lower endof said tube being such that the lower end of said holder is wedged intoand supported by said tube.

2. In a vaporizer for lindane, the combination comprising a generallycup-shaped body having an open end, said body being adapted to bemounted in vertical position with the open end thereof extendingupwardly, said body having air intake openings adjacent the lower endthereof, a tube mounted within said body and extending generallyvertically, electrical heating means adapted to heat the lindanecomprising a resistance coil wound around said tube, and a perforatedholder for lindane mounted within said tube, the internal surface ofsaid tube being generally circular and tapering upwardly, saidperforated holder being generally triangular in cross section, theinternal diameter of the lower end of said tube being such that thelower end of said holder is wedged into and supported by said tube.

3. In a vaporizer for lindane, the combination comprising a generallycup-shaped body having an open end and adapted to be mounted in verticalposition with the open end thereof extending generally upwardly, saidbody having intake openings adjacent the lower end thereof, a tubehaving an upper peripheral flange engaging the upper end of said bodyand thereby supportingsaid tube Within said body with the axis thereofextending generally vertically, said tube being in spaced relationshipto said body thereby' defining a generally annular space between saidtube and said body, said peripheral flange closing the upperend of saidannular space, electrical heating means adapted to heat the lindanecomprising a resistance coil wound around said tube, and a perforatedholder for chemicals lindane mounted within said tube, the length ofsaid tube being several times its diameter, the length of said holderbeing several times its largest cross-sectional dimension, said holderhaving portions of the side walls thereof spaced. from the inner surfaceof said tube, whereby air may circulate between said holder and saidtube.

4. In a vaporizer for lindane, the combination comprising a tube,meansfor mounting said tube in a generally vertical position, said tubebeing open ended whereby air may be passed therethrough in, a verticaldirection, electrical heating means adapted to heat the lindanecomprising a resistance coil wound around said tube, and a perforatedholder for lindane mounted within said tube, said perforated holderbeing generally non-circular in cross section, the internal surface ofsaid tube taperng upwardly and the internal diameter of the lower end ofsaid tube being such that the lower end of said holder is wedged intoand supported by said tube.

5. In a vaporizer for lindane, the combination comprising a tube, meansfor mounting said tube in a generally vertical position, said tube beingopen ended whereby air may be passed therethrough in a verticaldirection, electrical heating means adapted to heat the lindanecomprising a resistance coil wound around said tube, and a perforatedholder for lindane mounted within said tube, the length of said tubebeing several times its diameter, the length of said holder beingseveral times its largest crosssectional dimension, said holder havingportions of the side walls thereof spaced from the inner surface of saidtube, whereby air may circulate between said holder and said tube.

References Cited in the file of this patent UNITED STATES PATENTS2,472,992 Szekely June 14, 1949 2,660,828 Abrams Dec. 1, 1953 2,690,500Winberg et a1 Sept. 28, 1954 2,742,342 Dew et a1 Apr. 17, 1956 2,743,548Christopher et al May 1, 1956

